As is well known in the art, DIP devices consisting of a body portion, and attached and depending leads connected thereto for assembly into a PCB or the like, are manufactured with the leads disposed in a particular arrangement adapted for insertion in the predetermined array or pattern of holes or sockets in a PCB. The material of the leads and their connection to, and disposition on, the DIP bodies frequently results in a bending or distortion of the leads due to handling during manufacturing operations.
Since bent or distorted leads of DIP devices will prevent their insertion into predetermined arrays or sockets in a PCB, a need exists for apparatus which determine the integrity of DIP leads prior to insertion on a PCB. As a response to this need, lead straighteners were developed, such as that described in patent application Ser. No. 363,128 now U.S. Pat. No. 4,481,984 for ELECTRONIC COMPONENT LEAD STRAIGHTENING DEVICE, also owned by the assignee of the instant application. Without a device for determining lead integrity, proper orientation of DIP leads could only be assured by passing every DIP device through a lead straightening apparatus prior to insertion on a PCB.
One device presently known for determining lead integrity, provides a set of two photo sensitive devices aligned one over the other on an axis parallel to the axis of DIP leads which are in proper substantial parallel mutual relationship. DIP leads are caused to intercept a light beam directed at the photo sensitive devices by driving DIP devices past the photosensors through the use of a motor driven belt arrangement. An alternative way of visualizing the orientation of DIP leads and photo sensitive devices in such prior apparatus is to consider the path of travel of a DIP device on a trackway. DIP leads extend downward on either side of the trackway and are generally oriented perpendicular to the direction of travel of the DIPs. Two sets of photo sensitive devices are oriented on either side of the trackway along axes which are also perpendicular to the direction of travel. Improperly oriented DIP leads will deviate at an angle from this perpendicular orientation. Thus, as the leads pass in proximity to the photo sensitive devices, if the light to one of the photo devices is blocked while the other continues to receive light, there is an indication that the DIP lead is bent. The difficulties with such a system is that the motor and belts must be carefully regulated to maintain a constant speed while scanning occurs. Failure to maintain constant speed can result in false deviation determinations. Consequently, DIP devices which could be straightened and used, will be rejected and discarded, which indicates the inefficiency of such prior device.
A further known integrity determination device transmits light in a direction perpendicular to the path of travel of the DIP, i.e. beneath a trackway on which DIP devices travel, such that light from one source travels across the entire width of the DIP device to a photo sensor. It will be readily seen that if one row of leads is bent and one row of leads is in a proper orientation, such a prior system will indicate that all leads of a particular DIP device are acceptably oriented.
Thus, none of these devices can ensure lead integrity in all situations. Further, none of the above devices can assure that DIP leads are not bent inwardly, i.e. towards the center of the DIP. Such an orientation is also to be prevented to provide proper mounting of DIP devices to PCBs and the like.